'Unknown command' displays on all commands after installing Corridor EZ V27.02

This article applies to any customer using Civil 3D 2025 or 2026 platforms and the latest version of Corridor EZ (V27.02 or later)

Issue

After installing the latest version of Corridor EZ Topo, no commands are running.  All report back as 'Unknown command'.

This applies to users of the following CAD platforms:

• Civil 3D 2026
• Civil 3D 2025

Why is this happening?

Autodesk recently updated its 2025 and 2026 product lines to transition to the Microsoft .NET 10 runtime environment. Previous versions applied the Microsoft .NET 8 runtime environment.  Because this changes underlying system components, it impacts how older Corridor EZ settings files are handled, particularly settings migrated forward from legacy versions of Corridor EZ.

To address these issues, the latest version of Corridor EZ have been recompiled in the Microsoft .NET 10 environment (instead of .NET8).  What this means is that if you are not running the below versions of products then Corridor EZ will report 'Unknown command' when you try to run commands:

• Civil 3D 2025: Version 2025.2.7 or higher

• Civil 3D 2026: Version 2026.2.2 or higher

Note: If you are running Civil 3D (versions 2025 or 2026), type ABOUT into your command line to check your current build.

If your Autodesk version matches or is newer than the builds listed above, then the latest versions of Corridor EZ (V27.02 or later) will operate as expected.

Action

To resolve the 'Unknown command' issue, access your Autodesk account and update your Autodesk application/s. To do this:

• Oen a web browser and navigate to https://www.autodesk.com/au/account/home-v2
• Entering your Autodesk account details to login. 
• Click on Products and Services, then Product Updates
• Download and install the latest updates for your Autodesk product/s.

Autodesk highly recommend that you update all Autodesk products to the latest version to ensure that they all operate harmoniously with each other.